抄録
Cellulose is a polymer of 1, 4-β-glucan which is the most abundant organic substance on earth. It is deposited in crystalline microfibrils in the cell walls of higher plants during growth. Plant membranes may contain at least two UDP-glucose 4-β-glucosyltransferases, one with UDP-xylose that is involved in xyloglucan synthesis and the other may form cellulose. No one has not succeeded in the synthesis of cellulose at cell free system, although cellulose shouhd occur in plasma membranes. The question is “Where is the cellulose synthase in higher plants? and where do we go?”